Cobalt(II) complexes of new biomimetic polydentate amide: Spectroscopic, kinetics of thermal decomposition and XRPD studies

Complexes of Co(II) with new ligands N′,N″-bis(3-carboxy-1-oxoprop-2-enyl) 2-amino-N-arylbenzamidine (C21H17N3O6), N′,N″-bis(3-carboxy-1-oxopropanyl) 2-amino-N-arylbenzamidine (C21H21N3O6) and N′,N″-bis(3-carboxy-1-oxophenelenyl) 2-amino-N-arylbenzamidine (C29H21N3O6) have been synthesized and characterized by elemental analyses, vibrational spectra, electronic spectra, TOF-mass spectra, magnetic susceptibility measurements, thermal studies and X-ray powder diffraction studies. Vibrational spectra indicate coordination of amide and carboxylate oxygen of the ligands along with two water molecules giving a MO6 weak field octahedral chromophore. Electronic spectra and magnetic susceptibility measurements reveal octahedral geometry for Co(II) complexes. The elemental analyses and mass spectral data have justified the ML complexes. Kinetic and thermodynamic parameters were computed from the thermal data using Coats and Redfern method, which confirm first-order kinetics. Powder diffraction determines the cell parameters of the complexes.